The son of druggist in Tokyo, Furusawa was a dutiful soldier. Unlike his comrades, Furusawa was a man with an education, and so never quite fully accepted the blind obedience demanded by the Japanese military. When the United States launched a massive invasion to take back Hawaii in 1943, most of Furusawa's senior officers (including Takeo Shimizu) were killed. Furusawa decided to retreat (which was a somewhat dangerous decision) and keep fighting rather than rush forward and be killed by the enemy.

In the course of events, Furusawa found himself by the side of Imperial Japanese Navy commander Minoru Genda. While Furusawa admitted that he'd in effect retreated, Genda saw no reason to hold that against him. The course of the fighting brought both men to Iolani Palace. As American Marines prepared to storm the Palace, puppet king Stanley Owana Laanui shot his wife Cynthia Laanui and then himself. Genda committed seppuku, with Furusawa acting as his second, shooting Genda in the head after the commander had cut into his own belly.

Furusawa joined several Japanese troops in the basement of the Palace for their last stand. However, the Marines dropped grenades into the vents, stunning many of the Japanese troops, before going into the basement themselves. During the fighting, Furusawa was knocked unconscious and captured.

Furusawa was disturbed with becoming a POW, as he and his family had probably been dishonored. However, the fact that he'd been knocked unconscious and had not been in the position to fight to the death saved some of his honor. As a POW he was surprised at how humanely he was treated by the U.S., chalking it up to the U.S.' greater wealth. With Hawaii recaptured, Furusawa despondently realized that it was just a matter of time before Japan itself was defeated.